Lincoln Service Parts 2 › Lincoln Electric 9SS31648-2 HEX SOCKET PLUG - 1/4 NPT S31648-2 Lincoln Electric 9SS31648-2 HEX SOCKET PLUG - 1/4 NPT S31648-2 Sale Price: $4.06 Original Price: $4.67 HEX SOCKET PLUG - 1/4 NPT PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 1 Add To Cart Added! HEX SOCKET PLUG - 1/4 NPT PURCHASE PRICE SHOWN IS FOR A QUANTITY OF 1